Questions tagged [hydrogen]
Questions regarding the chemical properties of hydrogen and its behavior in reactions and compounds.
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What typically happens to H2 molecules released into atmosphere (with no spark source)?
I'm wondering what happens when $\ce{H2}$ leaks from say a transmission pipe in an unenclosed area. No immediate source of ignition, I know it rises more quickly than helium (x2 I believe) and ...
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Reliable automatic addition of hydrogens and charge assignment to small molecules at given pH?
I have some PDB structures of small molecules with missing hydrogens. Is there a software available that places missing hydrogens and assigns a charge to the molecule that is reliable? I am looking ...
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Why are hydrogen ions always associated with another molecule?
I was reading N.C.E.R.T. class XI part 2 book and chapter Hydrogen,when I came across this statement:
Loss of the electron from hydrogen atom
results in nucleus ($\ce{H+}$) of ~1.510–3 pm size.
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Comparing heat of hydrogenation per mole of butenes and 1,3-butadiene
The question asks us to select the compound with the smallest heat of hydrogenation per mole out of the following:
a) 1-butene
b) trans-2-butene
c) cis-2-butene
d) 1,3-butadiene
Since all four ...
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How to add hydrogens to a crystal structure?
PDB protein crystal structures most of the time lack hydrogen atoms. Usually I use PyMOL (h_add) but it does not always seem to be giving the correct result. What ...
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What is the bonding type in hydrides of group 2 elements?
In one of my MCQ questions, there was a statement saying all group 2 elements form covalent hydroxides. I know it is incorrect. I know that $\ce{BeH2}$ is a covalent hydride. What about the rest? Are ...
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Is there an electrolyte that will halt the production of Hydrogen in water electrolysis?
Care must be taken in choosing an electrolyte, since an anion from the electrolyte is in competition with the hydroxide ions to give up an electron. An electrolyte anion with less standard electrode ...
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What fraction of hydrogen in air results in an explosive mixture?
I would like to know if there is documented evidence of the quantity of hydrogen to air that must be present in the mixture to risk explosion or flame.
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Really how rare are hydrogen atoms?
Hasok Chang, a chemist, but perhaps more a philosopher recently published the book Is Water H2O? . Chang used the question and an extensive web of arguments ultimately as a platform to support a ...
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Equivalent hydrogens in 2,3-dimethylbutane
So while calculating for the relative yield of monochlorination for 2,3-dimethylbutane, I was counting the primary hydrogens, I counted 6, but in fact it was 12. Why is it 12? How do you find ...
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Hydrogen Fuel Cell and Battery
For hydrogen fuel cell to produce electricity, hydrogen will need to be supplied to the anode. To split oxygen and hydrogen from water and obtain hydrogen, we need to use electrolysis. To use ...
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Does hydrogen react with air at room temperature and pressure?
I have a container with 3% hydrogen and the rest is air. How fast will the hydrogen get oxidized by air?
How much will the reaction speed up with increased temperature?
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Why are so many wave functions associated with hydrogen?
According to Wikipedia, there's an infinite set of possible wavefunctions (orbitals) for the hydrogen atom:
$$\psi_{n\ell m}(r,\theta,\phi) = \sqrt {{\left ( \frac{2}{n a_0} \right )}^3\frac{(n-\ell-...
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Are the energies of orbitals that are not filled in an atom, equal?
In a hydrogen atom only 1s orbital is filled. Does this mean that the energies of all other orbitals are equal? If so,why?
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Calculating moles of Hydrogen gas in multiple gas container
If there was a 500 mL container filled with oxygen and hydrogen so it burns completely (2H:1O), how many moles of hydrogen gas would there be if there if pressure is 101.3 kPa and the temperature is ...
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